tree 0404a9aed3c147e2a0f4ec03eefb40572a9505b8
parent 18fbb93fbec3cfd6acf46f60990f7ab21c4221dd
author Alan Stern <stern@rowland.harvard.edu> 1310764935 -0400
committer Greg Kroah-Hartman <gregkh@suse.de> 1310808884 +0200

USB: OHCI: fix another regression for NVIDIA controllers

The NVIDIA series of OHCI controllers continues to be troublesome.  A
few people using the MCP67 chipset have reported that even with the
most recent kernels, the OHCI controller fails to handle new
connections and spams the system log with "unable to enumerate USB
port" messages.  This is different from the other problems previously
reported for NVIDIA OHCI controllers, although it is probably related.

It turns out that the MCP67 controller does not like to be kept in the
RESET state very long.  After only a few seconds, it decides not to
work any more.  This patch (as1479) changes the PCI initialization
quirk code so that NVIDIA controllers are switched into the SUSPEND
state after 50 ms of RESET.  With no interrupts enabled and all the
downstream devices reset, and thus unable to send wakeup requests,
this should be perfectly safe (even for non-NVIDIA hardware).

The removal code in ohci-hcd hasn't been changed; it will still leave
the controller in the RESET state.  As a result, if someone unloads
ohci-hcd and then reloads it, the controller won't work again until
the system is rebooted.  If anybody complains about this, the removal
code can be updated similarly.

This fixes Bugzilla #22052.

Tested-by: Larry Finger <Larry.Finger@lwfinger.net>
Cc: stable <stable@kernel.org>
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>